a, Microtubule stabilization by paclitaxel (PTX) inhibits non-core invasion of core domain. Left: Images of RPE-1 cells after drug treatment(s): Enlarged images from the boxed regions show the non-core (Nup133) gap on the main chromosome mass (red arrowheads). Right, top: Experimental scheme. Right, bottom: Quantification of the results (mean with 95% CI, n=40, 47, 41, 61, 40, 47, 41, 61, left to right, from 2 experiments). **** P < 0.0001, NS: P=0.2974, 0.9837, 0.2473, 0.3374 (left to right), two-tailed Mann-Whitney test. b, c, Small-scale core/non-core domain separation on lagging chromosomes after KIF4A depletion. b, Images of Aurora B-GFP-expressing HeLa K cells (2 technical replicates). Merged and enlarged image: Emerin (red, white arrowheads), Nup133 (green, white arrows). Synchronization as in Extended Data Fig. 1e. c, The fraction of lagging chromosome circumference covered with Nup133 in HeLa K cells (cartoon shown in left; mean with 95% CI, n=90, 52, 81, from 2 experiments). **** P < 0.0001, two-tailed Mann-Whitney test. Scale bars, 10 μm.